I've been reading some of the latest posts concerning the original front suspension. I've not removed mine yet on my '50 3100. My determining factor has to do more with cost than driveability. I know all the spring bushings will need replaced. I would also want to install 5 stud dropped disc brake spindles. In addition, I would have to find a proper steering box with power steering compatibility. I assume some if not all linkage would need to be repaired or replaced. There may be additional items I didn't list and as always the unforeseen parts that add up quickly. An IFS from Speedway will cost $600 for the bolt-on crossmember and approximately $1,400 for the rest of it if my memory serves me correct.
Do any of you want to weigh in on the comparative cost issue? Time I have, funds not so much!
Here's my 2 pennies worth. As far as the solid axle goes, you're not ever going to be able to duplicate the strength and durability of it. On a 60+ year old truck, you're probably going to have to replace the spring bushings and shackles. Not a huge deal. When it comes to kingpin bushings, as long as everything feels tight, you're probably ok. If you have to replace them, it's possible that you're opening up a can of worms. As far as power steering goes, I haven't really seen a kit out there for the solid axle, that I really like. The Toyota steering box setup is probably the best, but it's pricey and again, you're opening up a can of worms. There are vendors out there with front lowering leaf springs, of course this opens up a can of issues with pitman arm angles, etc... If you're looking for something stock, there are also vendors out there with OEM style leaf springs.
As far as IFS goes, the kits that are on the market now are plenty strong, not to mention there's a ton of aftermarket parts and options for them. The last car show I went to there was a couple dozen vintage trucks. Only 2 of them had the original beam axle, the rest were IFS suspensions, so there's plenty of folks out there that trust IFS on vintage trucks.
I know you mentioned the bolt on kit. I'm not familiar with it, but I know the Speedway kit looks identical to the old Chassis Engineering setup, which is now owned by Heidts. From everything I understand, it's a quality product.
On my 54, I was originally going to stick with the solid axle. Well, I changed my mind on what I wanted (about dozen times). I picked up a crossmember kit from CPP, it was only 200 bucks. I don't want a truck that's dropped to the ground, so I added a little material to the crossmember and trimmed the spring hats accordingly. I'm trying to be economical and I bought control arms and spindles from another vendor. In hind sight, I wish I would have bought the whole works from one place.
With an IFS setup, there's going to be no inexpensive way around it. Most folks doing an IFS are doing a complete drivetrain swap already, which I believe you're doing also. My advise is to call around and talk to some vendors and decide what's best for you. Most vendors can build a custom kit based on what you're looking for. I see you're in Iowa, maybe take a trip to Cedar Rapids and see the folks at Street Rod Engineering or even take a day trip to Wisconsin and talk to the folks at JW Rod Garage. Heck, they might even install the kit for you at a reasonable price.