The follow-on to my original is that I'm looking at a Mooney right now and wondering if I'll now need to get a complex sign off...

I have a current ATP ME, but only PPL for ASEL...why is it so hard to figure out the FARS? I've got time in the Mooney from early '80s...

If I get the plane, I'd probably get a CFI to go with me for a couple hours anyway, just to make myself feel better - probably get the endorsement then and eliminate any doubt.