Just swap in a 300 inline 6 and you'll notice a world of difference. My Bronco isn't affected by hills at all out on the freeway. Decent gas mileage & the ability to tow, tow, tow. Maybe get the 300 inline, drop some higher compression pistons and a 240 head, use the efi exhaust manifold & put at least 2 barrels of carburetion on the intake side and those pesky hills have been conquered.