Upgrading NT 5x8 to A-Frame Coupler and jack

I'd appreciate any advice on doing an upgrade to an a-frame coupler and jack on an Ironton (N. Tool) 5x8 bolt together trailer. I've found a coupler, but, I don't see an angle in the description.
https://www.amazon.com/gp/product/B006YEBSJS/ref=ox_sc_act_title_2?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
https://www.amazon.com/gp/product/B005DGK1D2/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
I'm specifically wonder if the angle of the coupler will match the a-frame angle on the trailer and if the jack will be too long to retract up far enough to eliminate damage. I realize this is a weld on coupler. I will drill the holes needed to attach.
TimC
https://www.amazon.com/gp/product/B006YEBSJS/ref=ox_sc_act_title_2?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
https://www.amazon.com/gp/product/B005DGK1D2/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
I'm specifically wonder if the angle of the coupler will match the a-frame angle on the trailer and if the jack will be too long to retract up far enough to eliminate damage. I realize this is a weld on coupler. I will drill the holes needed to attach.
TimC