Hi,
I don't take the Subframe out ................
I do them by using 4 x 500 mm lengths of Studding, weld a Nut on the end of each, then run another Nut right down next to that, (same thread as Subframe bolts obviously)
Remove one Subframe Bolt at a time, Screw the studs in one at a time about 8 to 10 turns each using the welded nuts, and then run the free Nut up to nip each corner of Subframe, then when you've got all 4 in, lower the Subframe by winding down the 4 Nuts evenly until enough room to get the Bolts out of the Arms to replace them
Note that I will always do all of the Arms both sides at the same time, use either Febi Bilstein or Lemfoerder Rear Arm Kit, fit them and forget them for another 15 years
HTH,