I checked the Painless web site and they do have a harness that appears designed for my exact combination of parts. The price is closer to $500 though I didn't shop for deals, just figured I'd chase using what I have before spending the bucks.
And I noted the TPI stuff too, though I'm not ready to part out my TPI car, I hope to keep drving it a few more years.
There are several 454 powered AD trucks that show up at local shows, so I know it can be done, and I've looked pretty hard at how various details were handled. Power steering has been part of my plan for quite a while and the kits that use a 70's pickup box in front of the axle looks like my answer.
The 454 is coming out of the pickup that until recently I used to tow my trailer, and I'm pretty much satisfied with the power in its current form. I expect the completed truck to weigh about 5,000 where the donor truck was closer to 6,000, so I'll gain a little performance there. On the minus side I'm using 3.73 gears where the donor truck has 4.11, so I'm trading off leverage against weight and hope performance stays in the acceptable range.
