I have a HF picker too. It will reach high enough with the arm out all the way. Problem?? The legs need to be pushed out all the way too, otherwise the rear would lift. They wouldnt fit in between the tires.
Fix... I made up a counter weight frame for the back side of the lift that I could load 750lbs worth of bagged gravel into. I actually did that to build my patio cover. I was lifting 6x16"x15' beams up twelve feet. I made a new arm that was fifteen feet long and even with the legs out it wanted to tip. The beam was prolly only 300-400lbs but WAY out there. So 750lbs on the rear of it worked great. Dangerous?? Looked like it, but hey, take it slow and it worked. Lifted 20 beams to that height.
So anyway, back to the simple engine lift, no problems.
I lifted a 2000lb mill off a trailer with the extendo arm too. Now that was scary, the arm was flexing, the ram was bouncing, my sweat was pouring. LOL I seem to get into alot of heavy one man lifts. My 4000lb lathe was fun to watch LOL
But an engine and tranny lift isnt anything to be lax about either, some iron there. I have used two straps going back to the tail of the tranny to support it too so its not just dragging on the ground. Once I just had my creeper under the tail and let it roll out on it. JR