ORIGINAL: sebo
You may have to add some weight to the nose to compensate for the tailwheel weight and the removal of the forward weight created by the nosewheel.
Be sure to check the CG.
Some of the nose weight will come out of the main gear moving considerably forward.
After removing the nose wheel and its linkage and installing the tail wheel an its linkage the main gears can be fastened temporarily (scotch tape or duck tape will do that) and its location for balance can be closely approximated.
That is of course if one is not building the whole airplane but just modifying an existing trigear.
To me, from "The Good Old Times" a taildragger looks like an airplane. A trigear looks like a kiddycar.
OK ___now, all join in and let's have a big laugh. Hee Hee !!!
<span style="color: #ff0000">Happy Holidays</span>
Zor