That's why i bought Dr. Feickert protractor. If your arm does not come with original template you need to measure spinde to pivot distance correctly. Your Denon tonearm fits Luxman tonearm base (model TP-SG) with single small mounting hole. Tonearm with larger shaft doesn't fit into this tonearm base hole. Luxman provided different tonearm bases for different arms, those bases goes for $200 each and quite rare and hard to find. TP-MT base made for tonearms fixed by 3 screws (fidelity research, saec, micro...). And for large armbase shaft (like Technics EPA-100, Victor 7045, Lustre 801) luxman made tonearm base with large hole, model TP-LH. There is also special luxman tonearm base for SME only, model TP-LS. So when you are looking for new tonearm make sure your tonearm base is compatible.