If it is any help, my KD messed up on the sink base cabinets as well which caused plenty of headaches for us. We ended up taking out the backs of the cabinets and then reinforcing them to get the sinks to hopefully fit!

Have you considered a Ticor from galaxy supply? They have a number of double sinks that fit into a 33" cabinet

Here is a link that might be useful: ticor sinks

Are the support pieces in the cabinet to support a sink? Still, 6" seems excessive... If so, you may be able to fit a 28" overall width sink. Or, if you're willing to cut into the support, maybe a 31" wide sink.

Did your KD know what sink you planned? Is it too late to have him/her reorder the correct size...i.e., is there a way to accommodate the extra 3" in your plan? Even if the cabinets have to be re-installed? I'm asking b/c if you answer "yes" to the above questions, I think your KD should not only order you a bigger cabinet, but should absorb the costs of not only the cabinet but also the labor to uninstall & reinstall the current cabinets, if necessary.

Sometimes it takes something like this to make someone actually learn from their mistakes. It's like with children, if you always "fix" their mistakes so there are no consequences, they don't learn... In this case, if it's always the customer who suffers and/or pays for the mistakes the KD makes, the KD never learns to do it right the first time!

Meanwhile, how about the sink I've linked below? If the rim is 1", that means you can have that 1" overlap on each side on the supports (which I think that's what the supports are actually for). That means a 31.5" sink - 2" = 29.5" left for the opening... If you can then cut approx 1.5" on each side, you will still have 1.5" or so support left on each side...in addition to the cabinet walls.

I do know that my sink has an overall width of 35-1/8" and it fit in my 36" sink cabinet without any modifications.

Here is a link that might be useful: Ticor S105D Undermount 16-Gauge Stainless Steel Double-Bowl Kitchen Sink

Rjr220, thank you for Ticor sink info! I am checking out Ticor's sinks and happy to know that several selections double bowl sinks available for 33" sink base cabinets.

Buehl, I am not sure what the purpose of support piece is. I think to reinforce the cabinet frame. I am willing to cut that piece to fit double bowl sink.
I have to answer Yes to all your questions. I told my KD that I need double bowl sinks from day one. You are so right about learning from the mistakes. I have no clue about the sink size until the granite guy came in for a template on Friday. My granite place supposes to provide a free sink, and I thought that I will get double bowl sink and dont need to worry about anything. I was totally wrong! I can't even get hold of my KD on Friday. He was out of the office on Friday for family emergency. I am going to reach out to him on Monday.
Thank you for Ticor 105SD sink info and link!

amon25 - I purchased the 31" single TicorS112 and it fit into my 33" base. I love it.

rufinorox I'm looking at the TicorS112 as well but am concerned that 10" will be too deep. What's your opinion on the depth?

Are there any single-bowl Ticors that are between 8 and 9 inches deep?

Thanks!

At first I thought I may have gone too deep, especially since I heard if you have an undermount you have to add an inch. I originally had an 8" and I thought it wasn't deep enough, persoanlly the 10: works fine for me. I think you'll like the look and size of this sink, its huge! There is enough space to wash large pans. Here's an alternative if you want to go with 9", but I wouldn't go with an 8".

http://www.overstock.com/Home-Garden/Ticor-Undermount-Stainless-Steel-Single-Bowl-Kitchen-Sink/3666365/product.html?rcmndsrc=2

Thanks rufinorox!

I bought the Artisan single bowl which is the exact same size and shape of the large Ticor but it is only 9" deep. I also like the grid better on the Artisan (larger holes). It is pricer than Ticor but the quality is very nice and in the scheme of the whole kitchen it was not a significant difference. I found the best price on Artisan sinks on Marmo Enterprises and I received it within a few days. Good luck!

Hi,
I had the same problem. I got a double bowl undermount
sink (stainless steel) 29 in. from Lowe's. No drain kit
included.

There are several Blanco double sinks that will fit into a 33" cabinet.

I would definitely have a double sink!

Here is a link that might be useful: wooden trash can