I would certainly suggest this as well. It's a step ahead of the Dana30 in strength, and is almost entirely bolt-on. You just need the donor axle and steering linkage from the correct Ranger or Explorer, and to shorten your front driveshaft one inch (it can be made fully 100% bolt-in if you also get a 1990+ front driveshaft & t-case, could be an opportunity to swap to a manual-shift t-case if yours is electric-shift).
If you're dead-set on a solid beam axle, then just keep in mind, a D30 isn't the best axle to use, but is still an upgrade over the D28. With the light weight of a BII (compared to, say, a Supercab Ranger), the D30 does have a chance of survival with 33" or so tires if you treat it well (35" tires if you find a '95 or newer D30 having the larger u-joints).