If you are getting the frame from Bird I’d give them a shout, they are really helpful and know a lot more than us. That said, I’d get the headset and a new shock from bird.
If you are getting the long travel version the forks will be shorter than the rear travel, the longer travel ones also tend to have a bit more pedal contact due to the lower bb height.
LT says 130 to 140mm travel up front.
Headtube length on the bird is m 110mm, medium long and large is 120mm.
I found with my TR hardtail the “cheap” forks didn’t keep up with the bike at speed, great for pootling but when trying they got confused!! :) I found with longer travel it absolutely flew.
Have fun.