Well being a bit disappointed with my first attempt i decided to have another go but positioning the rail to drip feed oil directly onto the valve head. See …….. https://mgb.tips/2020/09/27/extra-rocker-valve-lubrication-part-2/
I found another length of brake pipe with a 3/8″ UNF nipple on it but had to straighten it. To remove any stresses from work hardening annealed the pipe. I did this by slowly running a blow torch along the pipe heating it to red heat as i moved along and allowing it to cool naturally.
I took the rocker cover off and removed the previous rail and reshaped the new line as per photos – a socket is ideal to bend the pipe gripped in a vice. Marked and drilled the 1mm diameter holes and fitted the pipe in position with a support bracket half way along the rail
Went for a run in the car and then removed the oil filler cap – this time plenty of oil around the end of the rocker over the valve. Whist driving there was no sign of burning oil / blue smoke from the exhaust after over run – same when i revved the engine on my drive.
So will see if there’s any difference in tappet noise – will probably double check the valve gaps after a couple more runs and check the new pipework all ok.