First, your build is spectacular, congrats!
Mast steps were pretty simple units at the time of
Enterprise 1775 but sometimes sat differently depending on the size of the ship and the era.
Sizes are easy.......... From the contract:
MIZEN STEP ….. The Mizen Step to be sided 14 ½ ins, of sufficient Depth on the Keelson, The Arms 5ft 6ins long each, & bolted with 6 bolts of 1 ⅛ dia'r.
MAIN STEP ….. The main Step to be sided 1 ft 11 ins and 15 ins deep on the Keelson and of a length to slide easy by the Stantions of the Well.
FORE STEP ….. The Fore Step to be sided 1 ft 9 ins, in Length 10 ft 6 ins, bolted 6 bolts of 1 ⅛ dia'r
Keep in mind the main mast step is wedged in place so it can be moved fore and aft to adjust the rake of the mast. For the foremast step, it sometimes sat between two crutches, but from the original plans it appears this was not the case. I did just now notice that the foremast location was changed from the original location but I only have the low resolution plan so cannot make out the notes about this.
The mizzen step was sometimes also part of a crutch, but does not appear to be the case for
Enterprise. based on the contract which indicates one crutch and is separate from the step.
CRUTCHES In HOLD To have 1 Crutch in the Run Abaft the Mizen Step, sided 9 ins The Arms 5ft 6 ins long, & bolted with 7 bolts 1 dia'r.
Main mast step with wedges
General shapes of foremast step and main mast step. As the foremast step on
Enterprise is not bordered by crutches, I would go with the same basic shape as the main step. Shaping it to fit the is more of a challenge than the main mast step, but it helps to start by making a cardboard template based on the body plan drawing. It will get you close but then it gets to be fun getting the exact shape. Ignore the dimensions in the drawing below as it is from
Trincomalee, but the shape is typical. The following is from Peter Goodwin's,
The Construction and Fitting of the English Man of War.

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