[murphyv310]

Yes I'll post up a revised diagram soon.
Anode modulation with a modulation transformer is the accepted way to do AM and gives the best fidelity and modulation depth. Basically all you do is modulate the HT supply to the Anode and G2, via the high impedance side of the modulation transformer. In this case I'm not including the G2 as the G2 is used for the feedback loop for the xtal. The lower the anode volts the lower the output of course and the higher the depth of modulation.