Sounds right, "T" must be Top Dead Centre or TDC on no. 1 cylinder, and "A" for advance.
If it works, and doesn't make more than occasional pop-popping noises (which is normal), then leave it at that.
If not, you will have to hunt down the timing marks on the flywheel.
1945 GPW 258777 DoD March '45
1943 WC54 81672040 DoD 6 Nov '43 Hood No. 731019