Tire width issues and any other ideas...

[Yetibob]

I have a 79 Silverado 2 wheel drive 1/2ton that I picked up for $450 with clean title. I am going to do a 2.5 front and 4 rear drop kit on it. I have 15x10s in the back and 15x8s in the front. I would like to know what the max size tire as far as width goes that I can fit in the back. I am building it as a weekend street cruiser and fun time trial truck. Any info on any other items or ideas would be great as well. I am doing a full door shave with new mirrors. I'm going to be replacing the 305, not sure what with yet. I'm thinking of going big block but I haven't made up my mind yet. It will most likely be getting a black and red paint job once all the body work is done.