You could just go with swamps turnkey engines and be ahead of the game as those prices.include the labor to assemble the engine. Look into the turnkey I believe one is around 9000 and the other one is about 18000.
Chris. I'm running dual walbro pumps to my 238/100's and using both tanks . No problem keeping pressures at 65 at wide open throttle through the stock selector valve.
Subd. I have an idea of how to do this with valves but would need to know if there is a hot in the harness for the selector. I'll get back later today and explain my idea I looked into.
Gonna need 4" to clear without a problem. Rims your going to want nothing less than 4.25 backspace if I remember right. Maybe more I ran a 17 by 12 and just barely hit at full lock left so you may need more back spacing
Some of the viper alarms allow for two vehicle use . But finding someone to install remote start on a Manuel is going to be fun, most shops won't do it around here and if they do your signing a waiver of liability