first of all which beams do you have? 2wd or 4wd? if 2wd '89 and older came with forged beams which can be cut and welded. anything after that is cast and can NOT be cut and welded.
i would not extend the beams at all unless youre going to switch to coilovers. extending them with a coil spring will just put more leverage on the coil making it less effective, same goes for the shock too if in the stock location.
definitely extend the radius arm though and use a heim joint on the end of it for the pivot with a nice bracket on the frame. solo motorsports and giant motorsports have good options for these parts if you cant fabricate them yourself.
you wont need to go to swing steering immediately. once youre in the 16"+ travel range with extended beams, rad arms, and coilovers then swing steering will become a little more necessary to help save your weak link.... the front hubs.
i beams are not rocket science. they are a very simple front suspension system that is great for prerunner applications. its VERY hard to **** it up lol.