sealed beam units

[rhunter]

I replaced an 2 odd units last year with a matching pair bought from a well known accessory shop who were clearing out old stock. My car had failed MOT on headlamp check - despite getting them set. Just before MOT retest, I had headlamp alignment carried out again, this time the guy said that he could get no reading whatsoever! I have used this service many times with other cars without any trouble.
Does anyone have any experience of 'odd' sealed beams that are troublesome?
What reference or number on glass is correct for RHD minors? Are there options or is there just one to suit?
Thanks

[kennatt]

don't understand what you mean by getting no reading could you explain a bit more

[kittyfell]

Don't understand either - are the lights working? Just shine them on a garage door and adjust that way, Don't waste time/money paying someone to do simple things like this.

[mike.perry]

If they light up the hedge on the left when you dip them then they are the correct units.