combustion powered nail driver may be used with substitution of a suitable barrel 34 including a notch 35 a generally flat first feeding mechanism 36 here a magazine and a second feeding mechanism 38 a nail magazine alternatively one or both feeding mechanisms and the barrel may be formed integrally with the power driving tool here the notch 35 of the barrel 34 permits the cross member 8 to be held by the driving tool 32 while being fully inserted into one of the grooves 12 formed on a deck plank 2 as shown in fig7 the notch 35 also permits an upper nose or point 37 of the flat magazine 36 to be engaged into the groove 12 so that the gun 32 and magazine 36 are held substantially parallel to the joist 4 as noted above the power driving tool may include a positive stopper mechanism for aiding alignment of the fixing member and cross member prior to installation referring also to fig8 the notch 35 also exposes a portion of the most forward anchoring member 10 in the second feeding mechanism 38 so that the anchoring member 10 can be positioned directly adjacent the plank 2 to provide proper spacing between adjacent planks still referring to fig7 and 8 in some embodiments the first and second feeding mechanisms 36 and 38 are provided integrally with the barrel 34 to provide.