[QUOTE=hansen01;17073993]
Clearly I need to work on my speed so...
-I am riding about 80-100 miles per week in 3 rides. Is this enough?
-Should I be start specific training (sprints, hills, spinning) or does that really matter at this point?
-Is it better to ride with the group as long as I can even if it means limping my way back the last half of the ride?

My suggestions:
-Ride 5 (or 6) days a week for 150-200 miles;
-Attack the hills (enjoy the burn) and work on intervals (this really helps when the group suddenly accelerates);
-Ride with 2-3 groups and also solo and you won't be limping your way back for long.

Depending on your other training (crossfit, etc.) and your diet, your weight will probably drop despite your gain in leg muscle. I am approximately your height (6'2 1/2") and before cycling I was 190-200 and not "fat". After cycling my weight has dropped to 170-175, and I've increased my caloric intake to avoid dropping below 170.

You should have no problems meeting your goals.