Clarify what sort of 4spd you have. If it's the original stump puller then it's a top loader and you shouldn't have any linkages to worry about.
Fortunately it is stuck in the gear you want to start out on. Try wagging on the shifter when you get it to speed. In my experience a lot of easy wagging around on the shifter is the usual antidote. That has almost always worked for me, though it seems to always take a lot longer whenever there's people standing around watching you look like a fool.
I have no handbrake and always put mine into 1st or reverse after I've shut it off. Sometimes it doesn't want to engage the gear, imperfect alignment of the synchros or something, and in that case I'm always able to get it engaged by standing on the clutch and doing a sort of pelvic thrust that rocks the truck back and forth until the mainshaft has found a good alignment or whatever. This always works and always makes me look like a weirdo when I have to park it that way.
Anyway, have patience and good luck.
