Tone arm holes do not line up - best way to attach TT?

@mcmanus,

Are you sure you have a 12" arm???  A quick verification it to measure from the tonearm pivot to the end of the headshell - it should be very close to 12".  The next available size from Reed Reed 3P - Reed tonearms is a 10.5" - this arm is about 2" difference.  One item to be careful is that there is a difference between Mounting distance (which is likely what the template shows) and the Pivot to spindle distance which I addressed above.

You can post all the pics you want. Just have to start a system page. Like this https://systems.audiogon.com/systems/8367

Oh come on guys, you knew it was only a matter of time ...

@millercarbon has it totally right when he said make boards up for yourself. I bought a piledriver drill for £50.00 bought the drill bits about another £30 total (for 3 different size arms). If using wood use HSS. I have bought blanks of Walnut and also Polycarbonate. I like Polycarbonate to work with - which surprised me.

This bloody COVID 19 has had the effect of really sharpening up my DIY skills.

After all this, ensure your diamond is still on the cantilever! That could explain the gliding across the grooves.

To sum up, the following questions are up for grabs:(1) The definition of "P2P", a term mentioned by the OP in passing.  Which would possibly reveal that mcmanus is measuring pivot to stylus tip, not P2S.
(2) The actual effective length of the tonearm.(3) The (remote) possibility that the wiring is dragging on the arm wand, or I'll add another, that the pivot bearings are too tight, preventing free movement of the arm wand (although that would probably not result in the cartridge skating all the way across the LP surface).(4) Diamond tip has fallen off the cantilever; it happens.