GavinT remembers that our own Andy Harwood came up with what I thought was avery intriguing mod by replacing the stub axle and the rest of the driveline up to the tranny with VW sand rail parts. The stub axles are hardened (and maybe also used on Porsches?) and the CV joints are found on Porsche 944s. So far I haven't taken it any further than to get some of the particulars from Andy. Jmarkusic also posted about it here (
https://www.lotuseuropa.org/LotusForum/index.php?topic=4782.0). Because of the difference in the VW and Renault splines, I believe it requires you to sacrifice a pair of Renault CV joints on which you would modify in order to attach the VW/Porsche CV joints. Such a setup should be plenty strong enough for almost any motor likely to be installed in a Europa.
My setup came from Richard (at Banks) as an early twin link kit. Richard used a Renault CV joint on the tranny side (which provided the plunge in the half shaft and which I pin to the tranny output shaft) of the half shaft (which had to be fabricated for my car at a drive shaft shop) and a U-joint at the upright end. Apparently, he decided later that the CV joint wasn't really necessary so newer versions of his kit just have you not pin the inner u-joint as JB describes in his second option.
A buddy of mine made up a Richard Mann type twin link setup by anchoring the inner end of the upper link to the tranny and the outer end to upright/radius arm as described here (
https://www.lotuseuropa.org/LotusForum/index.php?topic=1724.0). My buddy has a 365 but I would expect it to be easily adapted to an NG3. I'm pretty sure he kept his stock Europa half shafts and u-joints. His inner u-joint is obviously not pinned. He doesn't have a lot of miles on his but it seems to be working pretty well. After all, it really isn't so different from Richard's twin link kit - it just doesn't require a special cross member.
I think the strongest option is the VW/Porsche - Andy Harwood setup but it's also the most complicated to do. The Lotus Supplies twin link (I believe JB has this) is probably the easiest to do and surely less expensive that the VW/Porsche route. The Richard Mann setup using the stock half shafts would be the least expensive but would require a bit of fiddling to get the geometry right.
For most of us (except for people like kram350kram) any of those three twin link options would be sufficient.
On the other hand, JB is correct that a twin link is not required for an NG3.