Ant: It's a simple 2 part question or request for information from a guy who might not have been there at the time. Not everyone on this board was in their teens in & living the life during the early 1980's , Matt & I were were fortunate enough to be there & doing it all here in Australia.
"What type of 3 piece cranks would anyone recommend to use on my TA?
Everyone but you , answered the question & offered up their thoughts on a set of suitable 3 piece cranks , in my haste I did make the mistake of suggesting some Takagi 1 piece cranks rather than using any alloy 3 piece cranks. I strayed from directly answering his question , my bad.
"What would be era correct?"
Again he's asking for backup to his first question , some guidance in building his 84 XL TA
"in the spirit of the times" or trying to keep a Vintage look to his bike.
I'm sure it has something about keeping your answers "on topic" in the FAQ here. If you don't care for building "era correct" bikes then why comment on a question where someone is asking for "era correct" information ?

Yeah we cut & cleaned up a few sets of shonky Skyway pedals & mounted their cages onto a NOS
set of Skyway pedals , these particular pedals have seen <400 light duty turns.Skyway graphite pedals
were a short lived product under race & street conditions. They deserve to be an "era correct trailer queen part" , that's all their good for , Black sealed bearing DX pedals are on the single pinch Flites now. 5 spoke THUG mags replace the first generation Campy Hubbed Graphites. Thats one very incorrect era confused XL TA that can now get thrashed around
as a rider today.
There's plenty of threads debating the merits of what constitutes or defines broad terms like "era correct" , "survivor" , modifying NOS parts etc etc , post your _opinions_ there , why not start a new thread , titled "Jet Black's a Jackass" & see how long it lasts on a friendly & helpful area like Vintage talk or the Tech & Restoration section.Post that thread in the Cafe , I don't go there & the moderators may let it ride in there.
Jason was asking a question & wanting information.
I don't know how old he is or what he was doing in the BMX world in the years leading up to 1984. So I gave him some answers to his questions & a few thoughts.
If you want to throw in your opinion , at least offer an answer someones question.
JB
BTW Keep on torching & welding the Hutch Trickstar you mentioned down to a Pit Bike , downhill racer , sidehack or whatever you want , it will make the existing overpriced & uncut Trickstars worth more.