Ralph is about right but what ever cost you come up with it most often than not cost at least double and takes three times longer than planed due to people changing their mind with things in the build. If you can handle that the end result will be worthy.
That list of repairs you have is common to these vehicles modified or not. Wheather they will cover it under warranty is another thing.Take it to someone who specializes in these cars with your list and get another quote.
Powerglides may not be a enjoyable box to use on the street but they do produce the results with enough power behind them in a well setup car. They have also been able to handle well in excess of a 1000hp + in built form for many many moons.
Whole pump assy or just new pump fitted to old unit?. Either way you need to do a pump pressure test at idle and at w.o.t. Most w/shops could test this pretty easily and would eliminate this as the cause or prove it to be the problem.
Backfires underload can be from lack of fuel. You really need to check fuel pressure at w.o.t with a guage .You say you have changed the pump but with what pump,new,s/h ? What did the new trans cost and where did you source it from.
Just have a look at the front support bar on the inside edge near the front of the intercooler and see how much of the lip has been removed to fit the Rapid cooler. I don't think it is going in as easy as you think, But if your handy with a grinder and some primer all is good. The battery swap should be straightforward. You may also have to tweak the a/c line a little for clearance near the cooler on the passenger side.
Thanks for the info guys, been thinking about a different front wheel for a while now. Turbotrana have you got a link to the p/n and where you got your wheel from please ? cheers
Innovate gear is good. I bought the lm-2 to use in multiple cars when road tuning but if I was only doing my own car that is the setup I would have put in.
Isnt there a fuel tank in the way on the passenger side or am I thinking of another bolt near the tank. It can only go in one way to clear the tank assy.