I would say stick to stock carb man, I've looked at all options, just get yours rebuilt and try to keep everything running in stock condition. These trucks have been running for 20 years, if you restore to stock like conditions your looking at another 20 years. The 2 inch should be good but the motor runs good with just opening up the breather a little by rerouting the pipe to the front of the grill instead of under the battery and add a K and N. A rebuilt carb can run about 450, k and n 30, then work on the exhaust, you can weld in any 2 inch.