I feel your pain - I have the reverse problem in that LHT gives me insomnia (and made me add bodyfat, tho also muscle), I tried adding carbs, and working out earlier in the day but nothing helped. Recently I've completely quit lifting workouts and just did for HIIT and this has finally worked - I've been having my best sleep in several years these last few weeks. That said, I accidentally IF'd yesterday (no time for more than a few bites) and did my HIIT - insomnia last night. It seems IF gives some people insomnia so if you're IF'ing you might try stopping.
Me: 39, 5'11", primal since Dec 2011, always been active (surfing, martial arts) but no athlete.
Currently: bw 78kg (17ish% fat?), Squat 102.5kgx5 , Bench 67.5kgx5, Deadlift 115kgx5 (July 2013)
If less is more is more even more?