2nd on GET a FSM .
It can be downloaded from the common Motor collective Site.
They have a section of Manuals and the 350 FSM is in there.
Also IF your rockers were NOT loose and free to wiggle (slightly) when you did your cam Chain Tension adjustment - it is NOT correct.
ALL (4) Rockers MUST be free to wiggle when setting the cam chain.
If NOT there is still tension on it.
It MUST be at it's max Slack point when adjusted.
The Best Time to set the Valve Clearance on a Rebuild is BEFORE you re-mount the motor.
But If it is already in Place I would suggest you release the Back End of the Gas Tank from the Rubber Holder and Lift the Tanks Tab above the Rubber Holder.
This will give you a significant increase in accessibility to the Intake Valves.
2nd MOST all Feelers sold today are too wide and will create interference when attempting to adjust the valves..
Take a set of SNIPS to your .002, .003, .004 & .005 Feeler Gauges and cut them in Half length wise.
The original HONDA Feeler Strips that came with the TOOL Kit were about the same as taking todays standard Feelers after doing just that.
Use the .002 (Intake) & .004 (Exhaust) Feelers to get the valves to JUST drag a little, with the feelers being able to slide in & out.
Then Use the .003 (on the Intake) as a NO-GO Gauge that will NOT slide in between the Valve Stem & the Rocker Tip.
Do the Same on the Exhaust with the .005.
What you want is the Correct Size to slide in with a TAD of resistance and the next larger size to NOT go in at all.
That is your setting point.