Outstanding man!!! What you see on the #5 cam bearing position is the bastards knocked it in too far! And that right there is exactly why so many of our customers have the "lifter noise" issue after they have an engine done!!!!
Not only is the feed hole to the bearing partially blocked, the channel to the lifter gallery will be restricted also.
Even if the service part bearing is perfectly installed, it usually overhangs the gallery feed slot a tad. That is why I fair that area in...to insure full oil volume to the lifter gallery.
Installing cam bearings in any engine is a very tedious operation. And because the cam bearings in the ihc-manufactured engines are critical in their "metering" function for both the rocker arm system and the hydraulic lifters, they are even more tedious to install correctly.
Many machinists and engine guys think we're fulla shit about this...but then once they have to eat one single customer job, they suddenly become experts. We work with folks from all over the world about this issue (you folks have no idea of the volume of requests for information we receive that are not through this forum!), then they wanna argue that this is not critical because "they don't have this trouble with fords or chevrolets". So...at that point I simply ask 'em "why did you contact us if you think you know what to do"??
I will say, that after inspecting hundreds of oem cam bearings knocked out of various engines, the original bearings for the most part are about 0.050" smaller in width than the common aftermarket replacements such as the durabond brand we use. Same for the clevites and other aftermarket replacements. Therefore, once properly installed with the oil holes perfectly aligned, some work is always needed at the lifter gallery slot(s). That is simply part of attention to detail that makes the difference between success and failure for an engine builder.
Let's move on, what to do about this now...
I do not advise simply having the machine shop knock the #5 on through the block and then trying to re-install it correctly. That bearing od was "reduced" when it went in, and if you try and re-use it, it will not be the proper dimension for retention in the saddle. And I bet your "machine shop guy" will tell you that my position is fulla shit too!
Cam bearings are only sold in sets of five. So obtaining a single bearing is out of the question for the most part unless someone has some pull with the bearing supplier, they are too inexpensive to mess with in that regard anyway.
An alternative...the block can be placed on a solid surface and the engine stand mounting head removed to allow full access to that #5 bearing position. Then the "short" knocker handle can be installed on the correct cam bearing arbor, then inserted into the bearing and carefully snugged up just as if you were installing the bearing in the normal fashion. Then using careful hits with a dead-blow hammer, that bearing could be moved backward and positioned correctly. That is what the machine shop would do to correct this mistake, they would not replace all of the bearings typically, they would begrudgingly shortcut this "fix".
But...you must now verify all the other bearing positions, you May find other problems as well. If so, that engine needs to go back to the folks that you paid to do this job correctly and they need to eat it!
Aren't ya glad you asked about the cam???
For some additional information regarding "cam bearings" and the tool used for removal and installation, check this thread:
http://www.forums.IHPartsAmerica.com/gas-engine-tech/3783-cam-bearing-questions.html