Ditch the LM317s in favor of a more modern part that lets you ground the tab, e.g. MIC29512.
whats the complementary negative regulator for MIC29512 if LM337 need to be ditched as well?
and here the silence comes....
all of the sudden there is no obvious replacement for such a "archaic" negative rail regulator...
Ditch the LM317s in favor of a more modern part that lets you ground the tab, e.g. MIC29512.
so for all of you guys who immediately suggest to ditch those "dinosaur" components... either propose a complete solution or stay silent
in this case please propose parts for both positive and negative rails.
furthermore - stop suggesting expensive and "modern" parts to everyone - please stop suggesting a $7 replacement (MIC29512) for a 50cent part (LM317) to hobbyists and beginners... if LM317 is capable of doing the job then that LM317 is good enough and there is no reason to replace it with a 14x more expensive part.
@ OP: regarding thermal pads... either go for the silicone pads, or for higher power dissipation go for mica pads with a good thermal paste.