You could always stick to your guns and dare to be different. If you can get a tough good L20 for next to nothing, maybe it is worth contemplating abit more. Way up the costs involved with any engine. If you discuss it over with an engineer and they are happy to certify it, whats to stop you? Whats it all cost for you to build a tough A series etc? Whats it cost to put coil overs in the front of the 1000 and make up a new crossmember and draglink that will meet engineer approval and solve the height problem of the L20 all in one?
Look at the costs before you pass it up.
Maybe then you could put that briefcase of extra money ( if there is any )in the back to overcome the weight issues.
Just some thoughts.
Cheers Steve.