Timing marks and tdc

You
I am doing a full upper engine gasket replacement on my 96 olds silhouetter gm 3.4, tore the engine down and cleaned baked and wet grease and oil for months, cleaned every part spotless by hand and painted every part, when I took the heads off the piston heads were coated with thick black charred sludge, I turned the harmonic balancer raising and lowering the pistons to clean them and the cylinder bores, now getting back on the van I decided to do my timing cover, rented the puller, cleaned the timing cover to factory new then painted, I forgot to line up the timing marks in my excitement of putting something back together besides the heads (which I did months ago) question is I have studied watched and read hundreds of hours on finding my tdc and putting my rockers and pushrods back in correctly, learned how to take the lifters out, disassemble clean and reassemble and have them lubed but not submerged cause of conflicting info, one should I soak my lifters before my zero lash and rocker torquing or leave them good and lubed but still springy, and two on tdc of the compression stroke of piston #1 should my timing marks be lined up before torquing? Cause I had to rent a puller tool for the balancer which I long ago returned and installed my cover with gasket and permatex high temp gasket maker then torqued all the bolts back down, guess I am trying to avoid redoing that timing cover gasket and renting a tool if I dont have to, can I just tdc each cylinder and be ok, I cant find any marks on the timing cover or harmonic balancer so I am guessing to line anything up would require buying a new timing cover gasket and re renting the hb puller tool